Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 7

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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Period Type:	instant

- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Definition

Refers to additional short-term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

+ References

No definition available.

+ Details

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Namespace Prefix:	wba_
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Balance Type:	credit
Period Type:	instant

- Definition

Refers to number of tranches during the period.

+ References

No definition available.

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Period Type:	duration

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- Details

Name:	us-gaap_LineOfCreditFacilityAxis=wba_Three64DayCreditAgreementMember
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Subsequent Events (Details) £ in Millions, $ in Millions	3 Months Ended
Subsequent Events (Details) £ in Millions, $ in Millions	Nov. 30, 2015 USD ($) Tranche	Dec. 18, 2015 USD ($)	Dec. 17, 2015 USD ($)	Nov. 30, 2015 GBP (£)	Oct. 27, 2015 USD ($)
Subsequent Event [Line Items]
Term of credit agreement	364 days
Senior unsecured bridge facility					$ 12,800
Number of tranches \| Tranche	2
Maximum [Member]
Subsequent Event [Line Items]
Debt to total capitalization ratio	0.6			0.6
Term Loan [Member]
Subsequent Event [Line Items]
Fees related to borrowings	$ 18
Amount borrowed \| £				£ 1,450
Term Loan [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Debt to total capitalization ratio	0.60			0.60
Additional Term Loan [Member]
Subsequent Event [Line Items]
Fees related to borrowings	$ 17
Tranche One [Member]
Subsequent Event [Line Items]
Term of credit agreement	3 years
Tranche Two [Member]
Subsequent Event [Line Items]
Term of credit agreement	5 years
364 Day Credit Agreement [Member]
Subsequent Event [Line Items]
Amount borrowed	$ 750
364 Day Credit Agreement [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Debt to total capitalization ratio	0.60			0.60
Additional Bridge Loan [Member]
Subsequent Event [Line Items]
Term of credit agreement	90 days
Subsequent Event [Member]
Subsequent Event [Line Items]
Senior unsecured bridge facility		$ 7,800
Additional senior unsecured bridge facility		2,000
Term loan amount		5,000
Subsequent Event [Member] \| Additional Term Loan [Member]
Subsequent Event [Line Items]
Term loan amount		450
Subsequent Event [Member] \| 364 Day Credit Agreement [Member]
Subsequent Event [Line Items]
Amount borrowed			$ 750
Subsequent Event [Member] \| Additional Bridge Loan [Member]
Subsequent Event [Line Items]
Senior unsecured bridge facility		$ 3,000